Compressor



Feb. 9, 1932. H. L. NASH 44,4

COMPRESSOR Filed Oct. 19, 1929 3 Sheets-Sheet 1 3 Sheets-Sheet 3 3% W Q/7w M l Ii the casing.

Patented Feb. 9, i932 UNITE STTES PATEN'Il OFFICE ltltlllttltil) ll). WASH, OF SOUTH: NORWALH, CONNECTICUT, ASSIGNOR T NASIB: ENGI- lt l'ElEFtllNG COMlPAINY, OF SOUTH NORWALK, 4C0IN'IN'EG'.I.`ICUT, A CORPORATION OF CONNEGKTICUT COMFRESSOR Application filed october w, 1929. fierial No. 400,900.

'this invention relates to air compressors or puuips ot' the rotary liquid-piston type and particularly to puinps or compressors ot this type which eniploy a rotor in comb nation with an endless revolvingliquid body or ring, the orbit of which is controlled by the rccentric shape of the Compressor casing 1n such a manner as to effect the compression of the air.,

lt is an object ot' this invention to provide a eompressor ot this general type wh1ch embodies means 'for increasing the final discharge pressure of the air by subjecting it to the inlluence ot a. supply or" high pressure waiter or other liquid in addition to the compressive force ot the liquid piston.

Jl `further object is to provide a unita device ot this class which includes in corn )ination un air Compressor of the type described and a liquid pump for providing the liquid under pressure 'for accomplishing the further compression ot the air.

?in the attainment ot these objects, this invention conteinplates the provision oit' a rotor which is provided with the usual shrouds at its sides connected by a series of vanes between wl'iich are 'formed displacement chamhers or buckets. This rotor is arranged to revolve in a casing ot' generally elliptical or ovui shape providing eccentric ortions or lobes of substantially crescent s ape at intervals around its pcriphery. The casing and the rotor huckets are provided with ports which register at certain points during the rotation for the admission and exhaust of air. als the rotor is driven at high speed the vanes import a rotary motion to the liquid which partly tills the casing and, due to the rcntrit'ugal force developed, this liquid assumes a ring shape and will alternately partiully rccede 'from the Chambers or buckets ot the rotor and return therein, as it is guided in its eeccntric orbit around the interior ot ls this rcvolving body of liquid recedcs trem the buckets upon reaching a lobe portiouoi" the casing, it draws air into the inner portion ot the buckets near the hub ot tiu` rotor through the registering openings or portc in the bucket and casing walls, and as the outer wall ot the casing again curves in toward the periphery of the rotor, the ports no longer register and the liquid ring upon again ncaring the center of the rotor compresses the air in the buckets until it is eX- pelled upon registry of the bucket ports with the outlet ports of the casin Between the points of greatest compression of the air du'rin r the movement ot the rotor, (that is, the point where the casing approaches closest to the periphery of the rotor), and the point where the bucket ports register with the outlet port, the outer wall of thecasing is cut away to provide an admission port: of relatively large arca for the high pressure fluid. Beyond this port the outer wall of the casing again converges from a spaced position with relation to the rotor periphery to a position nearly in contact therewith for the purpose of expclling the compressed air and a portion of the liquid through the registering bucket ports and casing outlet port. The mixed compressed air and excess liquid are carried to a se 'iarator from Whence the air is withdrawn for use or storage and the liquid is again pumped into the Compressor as before.

Other objects and features ot novelty will be apparent from the following specification when read in connection with the accompanying drawings, in which exemplary cmbodinients of the invention are illustrated.

Figure 1 is a diagrammatic view of one form of apparatus embodying the principles of the invention;

Figure 2 is a transverse' vertical cross section of the air Compressor shown in Figure 1 taken on the line 2-2; a

Figure 3 is a horizontal cross section taken on the line 3 -3 of Fig. 2;

Figure 4 is a Vertical sectional View taken on the line 4-4 of Fig. 3;

Figure 5 is a fragmentary diagonal cross section taken on the line 5-5 of Fig. 2;

Figure 6 is a diagonal cross section of another embodiment of the invention taken on a line corresponding to line 5-5 of Fig. 2; and

Figure 7 is a View similar to Fig. 2 showing a further modified form of the invention.

Referring more particularly to the drawings, the apparatus as disclosed in Fig. 1,

comprises an air Compressor designated generally by the letter A, a water pump designated `B and a water and air separator to which is' applied the letter C.

The air Compressor is shown in detail in Figs. 2 to 5 inclusive, and comprises a housing 5, the base of which constitutes the support for the Compressor. A rotor 6 is mounted Within the housing, and is secured as by keys 7 to the shaft 8, which is journaled in the bearings 9 for rotation in the direction of the arrow shown in Fig. 2. The rotor 6 comprises a hub 19 carrying a series of substantially radial blades or vanes 11, slightly curved in the direction of rotation and connected by shrouds 12 and 13, which form close enough to prevent the passage of any of the water between the casing wall and the outer ends of the vanes 11. The casing wall'is spaced from the ends of the Vanes at 20 to provide a clearance for the passage of the compressed air as well as the body of water comprising the liquid piston. The lobe' portions 22 and 23, however, are extended outwardly leaving substantially crescent shaped spaces between the rotor and outer casing wall at these points. A part of the outer wall of casing 19 between the portions 20 and 23 is cut away to provide an opening 25 communicating with an annular space 24 between the lobe casing 19 and the housing 5.

The housing 5' is provided with a chamber 26, as shown in Fig. 3, for the pressure water supply. This chamber is provided with an inlet 27 which is connected by a conduit 28 with the delivery pipe 29 of the water pump. Openings 30 afi'ord communication from the water supply chamber '26 to the annular space 24.

lOn the other side of the housing 5 are provided semi-Circular Chambers 31 and 32, which are separated by the partition wall 33. The chamber 31 is formed with an inlet passage' 34, to which the supply pipe 35 is connected. An elongated inlet opening 36 *is provided in the inner wall of the chamber 31 at such a point as to be continually in com-` munication with several of the bucket 'ports 18 as they rotate past said opening. A similar opening 37 slightly longer than opening 36 is formed in the inner wall of the chamber 32 .to provide an outlet for the casing 19. This outlet opening37 is: similarly continually in communication with several of the bucket ports 18 as they pass this opening near the end of their cycle of rotation from the inlet port 36. A discharge passage 38 leads from the chamber 32 and is connected as at Y39 with the discharge conduit 40 through which the water and compressed air flow to the separator C. The separator may be of any preferred type, and is provided with a discharge pipe 41 for the separated compressed air and a return pipe 42 is connected to the pump B so that a portion of the separated water may be recirculated to furnish the supply of pressure water for the Compressor.

In operation the casing 19 is initially partly filled with make-up water, and the slight additional amount necessary for replacing any losses or for cooling purposes is introduced into the air supply pipe 35 by means of the pipe 48. It is obvious that, together with the high pressure water introduced to the Compressor through the inlet 27, this make-up and cooling water will furnish an excess of water in the separator C over that needed for recirculation as pressure water, so an outlet 49 is provided in the separator which may be controlled by a ball fioat valve or other suitable means.

When the rotor 6 is driven by the shaft 8 in the direction of the arrow, as shown in Fig. 2, the body of make-up water assumes a ring shape and revolves within the casing 19, and due to the centrifugal force and the shape of the outer wall of the casing 19 portions of the revolving ring of water" wilLalternately approach and recede from the center or hub of the rotor 6. hen any one of the buckets 17 has just passed the outlet opening 37, it will be substantially filled with water due to the air havingjust been ejectedtherefrom and the revolving body of make-up water being at this point directed toward the center of the casing by the approach of the casing wall toward the peripheries of the rotor at 21.

As the ring of water constitutingthe liquid piston begins' to recede centrifugally from the bucket 17 upon reaching the' lobe 22, airis drawn into the buckets through the inlet port 36 of the casing and the bucket ports 18. Then when the ports 18 pass beyond the port- 36 and after the point of maximum capacity of lobe 22 is reached,

the casing wall begins to converge toward the rotor again causing the adjacent portion of the annular body of'water to again approach the center of the rotor compressing the air in the buckets 17. Th s cornpression due to the revolving liquid piston comprising-the body of make-up water attains its maximumas the rotor buckets 17 pass the point 20 of the casing wall.

When the buckets reach the opening 25 which affords communication between the casing 19 and `the annular space 24, the

high pressure water in this annular space pe ugas Qt eaerts a turther compressive force on the entrapped compressed air in the bucket. 'the speed at which the rotor is driven is regulated with respect to the pressure of the water in the space 24 so that the velocity energy ot the water in the bucket is great enough to prevent the passage in the space :El trem causing a hack-how hetween the portion of the lohe casing wall and the rotor ranes, even it a slightly greater clearance were provided between the periphery ot the rotor and the portion 20 of the casing wall.

When the huchet reaches a point opposite the edge ot' the lohe portion 23 of the casing wall its port 18 is in communication with the outlet opening 3?' and, due to the converging shape ot this portion ot the casing 'Wall, the compressed air and part of the water contained in the bucket is torced through the outlet opening 8?' into the outlet chamber 32 and thence through the discharge passage 38 and pipe t0 into the separator C. Here the water is removed from the water and air niixtnre and returns through the pipe 42 to the purnpB 'for recirculation. The separated compressed airpasses out through the pipe tl and is available to supply the various demands to which it may he subjected.

lin the term of the invention shown in Fig. ti., the water pump is contained within the same casing as the air pump. An impeller t3, such as is commonly used in centrifugal water pumps, is secured to the shaft 8 as by lreys tt in such a manner as to rotate with the shaft in the space between the housing .5 and the casing 19.

ln the operation of this 'form of the invention', water at' ordinary low pressure may be supplied at the intake 27 s0 as to fill the cham her 26. The impeller pumps the water from the chamber 26 into the space 24 around the casing 19, and maintains a steady pressure, which is applied to the air being compressed in the rotor 6 in exactly the same manner as shown in* Figure 2. In this case, of course, the pump B and its connection may be dispensed with.

Figure 7 shows a` modified form of lobe casing which* may be used with either of the previously described installations, that is, irrespective of whether the water pump is lorated within the same housing as the air compressing rotor, or constitutes a. separate unit 'which pumps the water from some distance into the housing. In thisform' of the inven` tion there `is inserted in the cut away portion of the casing wall, corresponding to the open ing 25 in Figure 2. the converging wall sec- 2 tion 4:7. This arrangement provides, instead of the single openingfi as in the previously described embodiment, two openings 45 and 46 'through which the high pressure water trem the annular space 24 may be supplied to the rotor buckets. The .convoi-ging outer wall pressed air is finally ejected by the aid of the converging wall 23.

Although the apparatus forming the sub ject of this invention has been specifically described and illustrated as'being used to compress air by the use of water as the compressing medium, it is to be understood that the device may be used to compress anygas or r um. Furthermore, the invention is not limz ited to the specific embodiments described and illustrated but includes all modifications and changes which may come within the scope of the appended claims.

Having thus described the invention what is claimed as new and desired to be secured by Letters Patent is:

1. The method of compressing air which consists in passing the air into a fluid displacement Compressor of the rotary liquid ring type, effecting an initial compression of the air therein, introducing additional liquid into the Compressor at high pressure at a plurality of successive points and subjecting said air to the action of said high pressure liquid whereby further compression of the air is efiected.

2. The combination with a fluid displacement air pump of the rotary liquid ring type having a lobed casing and a. rotor therein, a chamber adjacent said casing, means' for supplying liquld under pressure to said chamben, a rtion of the outer peripheral wall of said loh:

to said casing, whereby increased pressure may be applied to the air therein by said liquid under pressure.

3. In an air compressor, a casing with' a rotor therein adapted to apply an initial compression to the air in said casing, and a housing en'veloping said casing and containing liquid under pressure, portions of the wall of said casing being cut away at a plnrality of successive points to admit said liquid under pressure from said housing to the casing,

-of the wall of said casing being cut away affording communication between said casing d casing being cut away aflording an entrance for said liquid from said chamber and said liquid pump,whereby increased pres sure may be applied to the air in the casing by said liquid under pressure. a

5. The combination with a rotary air pump having a casing with a rotor therein, whereby the air is given an initial compression, and a housing enveloping said casing, a' liquid pump co-axial with said rotor shaft within said housing for supplying liquid under pressure to said casing, a portion of the wall ofsaid casing being cut away afiording communication between said casing and said ;liquid pump, whereby increased pressure may be applied to the 'air in the casing by said liquid under pressure.

6. Apparatus of the character described comprising in dombination, a fluid displacement air Compressor of the type employing a rotary liquid ring, said Compressor being provided with a lobed casing, a liquid pump in communication with said casing for supplying liquid under pressure 'thereto, whereby the pressure of the liquid is added to the air compressed by said air Compressor.

7. Apparatus of the character described comprising in combination, a rotary liquid ring air Compressor having a casing, a pump in communication with said casing for supplying liquid under pressure thereto, whereby the added pressure* of the liquid is transmitted to the air already under compression A by said liquid in said rotary air Compressor,

and a liquid and' air separator connected to the discharge of the Compressor and the intake of the pump, whereby the liquid for producing the high pressure may be separated and recirculated.

8. Apparatus of the character described comprising in combination, an air compressor having a lobed casing, a rotor therein, a housing enveloping said lobed .casing, and a liquid pump within the housing, said lobed casing having a portion of its wall cut away, whereby the pressure developed by said liquid pump may act on the air being compressed by the rotor.

9. Apparatus of the character described, comprising in combination, an air compressor of the rotary liquid piston type having a casing, a shaft journaled for rotation there in, and a rotor keyed to said shaft, a housing enveloping said casing, and a centrifugal liquid pump within said housing having an impeller keyed to the shaft of said rotor, said casing having a portion of its wall cut away whereby the pressure developed by said liquid impeller may act upon the air being compressed by said air Compressor. a

10. In an air Compressor, in combination, a housing, a casing within said housing adapted to contain a liquid, a rotorwithin said casing provided with shrouds and vanes which form an annular series of buckets within said rotor, lobes formed at spaced intervals around said casing, the arrangement of said parts being such that rotation of said rotor generates a revolving liquid annulus which is adapted to efiect compression of air drawn into said buckets, a chamber between said housing and said casing adapted to be suppliedwith liquid under high pressure, a portion of said casing wall being removed to provide communication between said cham` ber and the interior of said casing, whereby the pressure of the high pressure liquid may be transmitted to the air compressed by the action of said liquid annulus.

11. In an air Compressor, in combination, a housing, a casing within said housing provided with air inlet and outlet ports and adapted to be partly filled with a-liquid, a

chamber formed between said housing and said casing and adapted to be supplied with high pressure liquid, a rotor within said casing provided with buckets, ports in the walls of said buckets, lobes formed at spaced inter vals around the circumference of said casing, the arrangement 4 of said parts being such that rotation of said rotor generates a revolving liquid annulus which together with the walls of said buckets forms chambers which are adapted to expand as they pass a diverging portion of a lobe and contract `as they pass a converging portion of a lobe, said air inlet port of said casingbeing adapted to register with the ports of said buckets as they pass the diverging portion of a lobeand the outlet port being adapted to register with the bucket ports as they pass the converging portion of the next succeeding lobe, the diverging portion of said last named lobe being cutaway to provide communication between said high pressure liquid chamber and said casing, whereby the pressure of said liquid may be transmitted to the air compressed by the action of said liquid annulus.

12. In an air compressor in combination means including a rotary liquid ring piston for compressing air therein, and means for admitting high pressure liquid to said compressor ata plurality of successive points during the compression of said air.

13. Apparatus of the character described, comprising, in combination, an air pump or a Compressor of the rotary liquid ring type, said pump or Compressor being provided with a double lobed casing, a rotor adapted to operate in said casing, one of the lobes of said casing being provided with an air inlet port, a liquid ring generated by the movement o said rotor and adapted 'duringthe operation of the device to eflz'ect the initial compression of the air within said lobe, means for introducing liquid under pressure to the other manise said pump or compressor being provided 'with a double lobed casing, a rotor adapted to operate in said casing, one ot the lobes ot said casing being provided With an air inlet U port, a liquid ring generated by the move ment of said rotor and adapted during the operation of the device to efiect the initial compression of the air Within said loloe, a portion ot the outer peripheral Wall of the other lobe being cut away to admit additional Water under pressure to said casing to efi'ect a *further compression of the air, and an outlet port in said second named lobe. H v 15. 'lfhe combination set forth in claim 1d' l@ in Which a Wall section is inserted in the space provided by said cut-away portion of the 'Wall ot said second named lobe and is spaced from the edges of the remaining Wall r portions so as to provide a plurality oii inlet lw openings for said liquid under pressure, said 'Wall section converging toward the periphcry ot said rotor in the direction ol rotation thereof. F\ lG. ln au apparatus of the class described, la@ an air coinpressor ol? the rotaryliquid ring type, comprising, a rotor, a rotor casing, a lobe formed in said casing Whereby the liquid ring generated by the movement of said rotor is caused to edect an initial compression ot the air in said casing, all of the liquid torming said ring remaining in said lobe during the compression of the air therein, a source ot liquid under pressure, means 'lor W introducing said last named liquid into said W casing ata point beyond sa1dlobe,and means tor euliausting said air and a portion of both ot' said quantities oi liquid from said casing.. li lju an apparatus of the class described, an air Compressor oit the rotary liquid ring type, comprising a rotor, a rotor casing, a lobe lormed in said casing, 'Whereby the liquid generated by the movement of said rotor is caused to effect an initial compression oit" the air in said casing, all of the liquid ::Forming said ring remaining in said lobe during the compression ot the air therein, a pump ior applying liquid under pressure, means for introducing said last named liquid into said casing at a point beyond said lobe, port for enhausting said air and a portion oit" both oit said quantities of liquid from said casing, and a liquid and air separator connected to said exhaust port and the intake ol said pump, Whereby the liquid *for producing the added pressure may loe separated and recirculated,

lin testimony Whereot ll hereunto alfin my si gnattur HARULD lll.. WASH,. 

